Starting attachment for edison phonographs



June 8 1926.

R. THOMPSON STARTING ATTACHMENT FOB. EDISON PHONOGRAPHS Filed May 4:,1925 Patented June e, i925.

UNITED STATES una PATENT FFlCE.

ROBERT THOMPSON, OF ILON, NEW YORK.

Application filed May 4, 1925.

My invention relates to a new and useful device for properly positioningthe stylus or diamond point of an Edison phonograph, over the outer endof the sound groove, so that lowering of the tone-arm-and-hornunit willproperly engage the stylus with the beginning of the record.

lt is one object of the invention to provide for obtaining the desiredresult in an exceptionally simple and inexpensive manner, and anotheraim is to provide an attachment for an ordinary Edison phonograph, whichmay be easily applied and adjusted to limit the swinging of theabove-named tone-arm-and-horn-unit, toward the center of the recordtable, to a position at which the stylus is directly over the outer endof the sound groove, whereupon lowering of said unit will position thestylus in the groove.

United States Patents 1,184,333 of May 23, 1916, and 1,211,573 ofJanuary 9, 1917, show the general type of Edison phonograph with whichmy invention is usable.

With the foregoing in view, the invention resides in the novel subjectmatter hereinalter described and claimed, the description beingsupplemented by the accompanying drawing.

Figure 1 is a perspective view of an Edison phonograph equipped with theinvention, the cover being swung upwardly and the front panel beingremoved.

Figure 2 is a detail horizontal sectional. view showing the invention intop plan.

Figure 3 is an enlarged vertical sectional view on line 3h3 of Fig. 2.

Figure a is an enlarged detail horizontal section on line l-e of Fig. 3.

ln the drawing above briefly described, U designates the well knowntone-arm-andhorn-unit of an Edison machine, provided with the usualdiamond point reproducer it for co-action with a record R on the rotarytable T. The unit U is mounted in the well known manner on a verticalshaft S having an operating handle H at its upper end, by means of'whichthe unit may be raised and lowered, the shaft also acting as a pivot toallow said unit to swing horizontally. In the form of my inventionherein disclosed, it co-acts with the front end of the horn of the unitU and is mounted on the bottom B of the compartment C in which alloperating parts are located. The construction shown is here- Seral No.27,886.

parts are so positioned that when the unit Y U is raised and the stylusof the reproducer E is clear of the record, the stop 4 is in the path onwhich the horn must travel when the unit U is horizontally swung toposition the reproducer R over the outer edge of the record, and by thetime swinging of said unit has taken place to the necessary extent todispose the stylus directlyv over the outer end of the sound groove, thehorn abuts the stop and thus can move no further at that particulartime. Thus, when the handle H is operated to lower the unit U, thestylus necessarily engages the outer end of the sound groove. Thisdownward movement of the unit U, disposes the horn below the stop el, sothat said unit may swing in the direction of the arrow inFig. 2 toeffect playing of the record. lV hen the playing operation is over andthe handle H is again depressed to elevate the unit U, this unit liftsthe arm 1 about its pivot 2 and when said unit is returned to its idleposition at the right-hand side of the cabinet C, the stop 4- drops fromthe horn and stands in readiness to again function.

ln the preferred form of construction, the post 3 is stamped froml asingle piece of sheet metal, into channel-shape, and this post isprovided with a horizontal base 6 having a slot 7 to receive anattaching screw 8, driven into the cabinet bottom B, the slot permittingthe necessary adjustment of the device when it is initially installed. l

lThe arm 1 is preferably formed alsoV of a single piece of sheet metaland the stop 4 is formed by downwardly bending the outer end of thisarm. To reinforce the arm, it is provided with vertical longitudinalflanges 9 whose inner ends are pivoted to the post 3, and to limit thedownward swinging of said arm, its inner end is bent downwardly toprovide a stop 10 which abuts the post 3 as shown clearly in Fig. 3.

In order to attach the pad 5 to the stop 4t, the latter is preferablyformed with-two vertical slots 1l through which the ends of the pad arepassed, said pad being preferably formed of leather,althoug`h this isnot essential. To hold the ends of the pad in the slots 11, the metalatfthev outerV sides of these slots may well be bent inwardly to anyrequired extent.

It will be seen from the foregoing that the inventionis extremely simpleand inexpensive,yet that itis efficient, reliable, and may be easilyinstalled and adjusted.

AExcellent results have` been obtained from the exact details disclosed`and they are therefore preferably followed. However, as above stated,modifications may of course be made within the scope of the invention asclaimed.

Il claim: l

l. Incombination with arphonograph having a record table'and atone-arm-and-hornunit, the latter being mounted for vertical movementand forhorizontal swinging; a stop adapted to abut a portion of saidunit whenthe latter is manually swung inwardly s sufficiently to disposethe usual stylus at starting position with respect to a .record on thetable, and supporting means for said stop preventing descent ofthelatter when the above-named unity is lowered to engage the stylus withthe record, Ithe aforesaid portion of said unitv being movable undersaid stop throughout thek record playing operation,- said stop beingadapted to be immediately lifted by said unit when the latter is liftedand sustained thereby while said unit is being swung to inoperativeposition, said stop being then adapted to drop to operative'positioinfin readiness forfurther use.

2'; Incombinati'on4 with a graphophone having a record' table and atone-arm-and-horn unit, the latter being mounted for vertical movementrand' for l'i'orizontal1 swinging; a stop adaptedv to abut the outerendof the horn of said unit when the latter is manually swung' inwardly to4dispose the usual stylus at starting positionwith respecttol a record onthe table, and' supporting means for the stop preventing descent of thelatter when theabove-nam'ed unit is lowered to engagey the stylus withthe record,- said hornv being movable under said stop throughout therecord playing operation and being effective to lift said stopand'sustain'itwhen said unit islifted and swung to inoperative position,said stop being then adapted to drop to operative position, in readinessfor further use;

The combination defined in claim l, in which said stop is formed by thefree end of a pivotally mounted vertically swingable ar'n'i,saidarnrl'iaving a stop for limiting its downward movement, but beingfree to swing' upwardly.

4. A device ofthe class described comprising-a support adapted to bemounted in outwardly spaced relation with the horn of a-tone-arm-and-horn-unit of a graphophone,

adapt'edito abiit'the horn wlienthet'one-arm and horn-unit is positionedto dispose its stylus over the outer end' of a record groove, said armhaving a stop adaptedto strike said support and limit the downwardswinging of said arm. t

6.*A structure as p specified in claim 4f; said vsupportcomprising apost having a base adapted to be secured upon the bottom of a phonographcabinet'. t Y

7. A device of the class described comprising a vertical post havingahorizontal `base formed with a longitudinal slot, said slot beingadapted to'receive a screw for securing the base to' thebottom of agraphophone cabinet in outwardly spacedrelation with the horn of atone-arm-and-liorn-unit, asubstantially horizontal arm pivoted to thevupper end of said post on a transverse horizontal axis, the inner end ofsaid arm having. a downwardly extendingstop to abutthe post and limitthe descent of the arm, the outer end of said arm havingr a stop to abutthe above-named horn.

8. In a graphophone stylus-positioning device, a metal stop having apair Vof` spaced parallel slots, a pad at one side of said-stop havingits ends passed through andheld in .said slots, and means for mounting'said stop withthe paddisposed to abut'a carrying lpart for the stylus.

In testimony whereof I have hereunto aiiixed my signature.

ROBERT THOMPSON.

lOl

